A major component in many biochemical investigations is the ability to identify complex mixtures containing thermally labile and involatile compounds which are not amenable to common identification techniques, such as gas chromatography/mass spectrometry (GC/MS), and gas chromatographic/Fourier transform infrared spectrometry (GC/FT-IR). The key to dealing effectively with such complex mixtures appears to be with a combined approach involving an effective "non-threatening" chromatographic separation, followed by a highly selective identifying tool. The use of high performance liquid chromatography for numerous molecular types of biochemical interest is already well established in the separation role. However, the appropriate detectors to follow the separations are not so well established. A central component to any such system is an effective interface, which will allow total solvent removal from the chromatographic effluent, whatever the solvent composition or gradient. The MAGIC (monodisperse aerosol generation) interface has been demonstrated to meet this need extremely effectively for many molecular types amenable to mass spectrometric identification. FT-IR spectrometry, on the other hand, has been underutilized in biochemical studies to date to a large extent because of an unfulfilled need for effective LC/FT- IR interfacing. The work described in this proposal addresses the need to develop a truly versatile LC/FT-IR interface, based on the MAGIC principle. The work will involve both fundamental and applied investigations. Key goals will be high interface efficiency, good optical design and effective data interpretation. The ultimate goal would be to develop an effective combined MAGIC-LC/FT-IR/MS system. Such a system would provide enormously powerful identifying power for mixtures of biochemically important molecules.